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1.
Inorg Chem ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39001841

RESUMO

Monitoring levels of excessive aluminum ions (Al3+) is crucial as it can harm the immune system, reduce enzyme activity, cause cell death, and damage environmental and biological systems. Developing a fast and efficient Al3+ ion determination method is the key to addressing this issue. In this work, red-emitting fluorescent copper nanoclusters (CuNCs) were synthesized using N-acetyl-l-cysteine (NAC) as a ligand and CuCl2·2H2O through a facile procedure. The NAC-CuNCs exhibited a large Stokes shift and displayed remarkable luminescence properties. A method for detecting Al3+ through a fluorescence probe was proposed. Its fluorescence mechanism was also explored. The probe showed rapid responsiveness (within 1 min) to Al3+ ion determination. The detection limit for Al3+ was found to be 19.7 nM, which is significantly lower than the WHO's value and most reports, with a linear range of 0-52.9 µM. The determination of Al3+ concentrations in actual water using the fluorescence probe yielded satisfactory outcomes. Moreover, the visual detection of Al3+ ions was also achieved through a smartphone, which can enhance its fast and practical detection.

2.
Front Chem ; 12: 1426865, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39036659

RESUMO

Introduction: Smart multifunctional surfaces targeting intricate biological events or versatile therapeutic strategies are imminent to achieve long-term transmucosal implant success. Methods: This study used dopamine (DA), graphene oxide (GO), and type IV collagen (COL-IV) to construct multilayer nanofilms (DGCn) based on their universal adhesive and biomimetic properties to design a versatile and bioactive titanium implant. The characterization of DGCn on different titanium surfaces was performed, and its loading capacity, release profile, in situ gene delivery, and in vitro biological properties were preliminarily evaluated. Results: Our results demonstrate that hydrogenated TiO2 nanotubes (H) provide a better platform for the DGCn coating than machined Ti and air-TiO2 nanotubes. The H-DGC10 displayed the most stable surface with excellent loading capacity, sustained-release profile, and in situ gene transfection efficiency; this could be due to the high specific surface area of H and GO, as well as the functional groups in H, DA, and GO. Moreover, the H-DGC10 exhibited good biocompatibility for human oral epithelial cells and promoted the expression of integrin ß4 and laminin 332, both being hemidesmosome-related proteins. Discussion: Our findings suggest that H-DGCn can be designed as a smart multifunctional interface for titanium implants to achieve long-term transmucosal implant success and aid in versatile therapeutic strategies.

3.
BMC Oral Health ; 24(1): 824, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033148

RESUMO

BACKGROUND: Excessive inflammation is a major cause of implant failure. The surface morphology, hydrophilicity, and loading of biomaterials are major properties modulating anti-inflammatory macrophage activation. This paper investigates the regulatory effects of modifying the surface of Titanium dioxide nanotubes (TNTs) with graphene oxide (GO) on the polarization of mouse monocyte macrophages (RAW264.7). METHODS: TNT was produced by the anodic oxidation of titanium. GO was subsequently electrodeposited on the TNT to obtain a TNT-GO composite. The samples were characterised through scanning electron microscopy (SEM), Raman spectroscopy, and X-ray diffraction. RAW264.7 cells were separately seeded onto the surface of three groups of samples: pure Ti, TNT, and TNT-GO. Under the condition of lipopolysaccharide stimulation, the influence of the sample surfaces on the gene expression profiles was investigated through RNA sequence analysis. In addition, cell spreading was observed through SEM, cell adhesion and proliferation were analysed using the CCK8 assay, and the expression of inflammation-related factors was investigated by ELISA and cellular immunofluorescence staining. The production of reactive oxygen species (ROS) in the RAW264.7 cells on the surface of the three groups was detected via immunofluorescence staining. RESULTS: The CCK8 results indicated that the adhesion and proliferation of the RAW264.7 cells were reduced on the TNT and TNT-GO surfaces. ELISA results revealed significant differences in the pro-inflammatory factors tumour necrosis factor-α and interleukin-6 secretion among the three groups at 24 h (p < 0.05). The secretion of pro-inflammatory factors significantly reduced and the expression of anti-inflammatory factor IL-10 increased on the TNT and TNT-GO surfaces. The RNA sequencing, ELISA, and cell immunofluorescence staining test results suggested that the inflammatory response of M1 polarization was reduced and the M2 polarization of macrophages was induced on the TNT-GO surface, which may be attributed to the reduction in ROS production. CONCLUSIONS: Under lipopolysaccharide stimulation, the inflammatory response of the RAW264.7 cells was reduced and the M2 polarization of macrophages was promoted on the TNT-GO surface, which may be caused by the reduced ROS production. Consequently, the designed TNT-GO material is promising for implants owing to its excellent inflammation regulation ability.


Assuntos
Grafite , Macrófagos , Nanotubos , Espécies Reativas de Oxigênio , Titânio , Grafite/farmacologia , Animais , Camundongos , Macrófagos/efeitos dos fármacos , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Inflamação , Adesão Celular/efeitos dos fármacos , Propriedades de Superfície , Lipopolissacarídeos , Microscopia Eletrônica de Varredura , Proliferação de Células/efeitos dos fármacos , Análise Espectral Raman , Difração de Raios X , Ativação de Macrófagos/efeitos dos fármacos
4.
Polymers (Basel) ; 16(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39000732

RESUMO

Most toughening methods for epoxy resins are usually used at the expense of other properties. Some polyhedral oligomeric silsesquioxanes (POSSs) with both a rigid Si-O-Si structure and flexible organic chain segments could be expected to be effective toughening agents. In this study, three reactive polyhedral oligomeric silsesquioxanes with a thiol group (OMPPS), a carboxyl group (OCOPS), and an epoxy group (OGCPS) were synthesized and characterized. They were utilized as modifiers to toughen 3-(oxiran-2-ylmethoxy)-N,N-bis(oxiran-2-ylmethyl)aniline (AFG-90MH)/4,4'-methylenebis(2-ethylaniline) (MOEA) (epoxy resin) with different molar ratios to obtain hybrid resins named OMPPS-EP-i, OCOPS-EP-j, and OGCPS-EP-k. The effects of the amount of modifier added and the length of the organic chain on the cage structure on various properties of the hybrid resins were investigated. The results show that all three modifiers show good compatibility with the epoxy resin. The hybrid resins have a low viscosity at 45~85 °C and can be cured at a low temperature (110 °C). The cured hybrid resins display improved toughness. Typically, the critical stress intensity factor (KIC) and impact strength of OGCPS-EP-0.6-C are 2.54 MPa∙m-1/2 and 19.33 kJ∙m-2, respectively, which increased by 58.75% and 22.48% compared with the pristine epoxy resin, respectively. In addition, the glass transition temperature and flexural strength of the hybrid resins are basically unchanged.

5.
Chem Sci ; 15(28): 11134-11144, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39027283

RESUMO

Electron injection effectively induces the formation of a 1T-rich phase to address the low conductivity of MoSe2. Nevertheless, overcoming the inherent metastability of the 1T phase (particularly during the conversion reactions that entail the decomposition-reconstruction of MoSe2 and volume expansion) remains a challenge. Guided by DFT results, we designed a composite with bimetal selenides-based heterostructures anchored on reduced graphene oxide (rGO) nanosheets (G-Cu2Se@MoSe2) to obtain stabilized 1T-rich MoSe2 and enhanced ion transfer. The construction of 1T-rich MoSe2 and built-in electric fields (BiEF) through electron transfer at the heterointerfaces were realized. Moreover, the rGO-metal selenides heterostructures with in situ-formed interfacial bonds could facilitate the reconstruction of the 1T-rich MoSe2-involved heterostructure and interfacial BiEF. Such a dual heterostructure endowed G-Cu2Se@MoSe2 with an excellent rate capability with a capacity of 288 mA h g-1 at 50 A g-1 and superior cycling stability with a capacity retention ratio of 89.6% (291 mA h g-1) after 15 000 cycles at 10 A g-1. Insights into the functional mechanism and structural evolution of the 1T MoSe2-involved dual heterostructure from this work may provide guidelines for the development of MoSe2 and phase-engineering strategies for other polymorphistic materials.

6.
Plants (Basel) ; 13(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38891305

RESUMO

Vaccinium duclouxii, a wild blueberry species native to the mountainous regions of southwestern China, is notable for its exceptionally high anthocyanin content, surpassing that of many cultivated varieties and offering significant research potential. Glutathione S-transferases (GSTs) are versatile enzymes crucial for anthocyanin transport in plants. Yet, the GST gene family had not been previously identified in V. duclouxii. This study utilized a genome-wide approach to identify and characterize the GST gene family in V. duclouxii, revealing 88 GST genes grouped into seven distinct subfamilies. This number is significantly higher than that found in closely related species, with these genes distributed across 12 chromosomes and exhibiting gene clustering. A total of 46 members are classified as tandem duplicates. The gene structure of VdGST is relatively conserved among related species, showing closer phylogenetic relations to V. bracteatum and evidence of purifying selection. Transcriptomic analysis and qRT-PCR indicated that VdGSTU22 and VdGSTU38 were highly expressed in flowers, VdGSTU29 in leaves, and VdGSTF11 showed significant expression in ripe and fully mature fruits, paralleling trends seen with anthocyanin accumulation. Subcellular localization identified VdGSTF11 primarily in the plasma membrane, suggesting a potential role in anthocyanin accumulation in V. duclouxii fruits. This study provides a foundational basis for further molecular-level functional analysis of the transport and accumulation of anthocyanins in V. duclouxii, enhancing our understanding of the molecular mechanisms underlying anthocyanin metabolism in this valuable species.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38863365

RESUMO

OBJECTIVES: Pseudomonas aeruginosa and Acinetobacter baumannii are ranked as top-priority organisms by WHO. Antimicrobial peptides (AMPs) are promising antimicrobial agents that are highly effective against serious bacterial infections. METHODS: In our previous study, a series of α-helical AMPs were screened using a novel multiple-descriptor strategy. The current research suggested that S24 exhibited strong antimicrobial activity against major pathogenic bacteria, and displayed minimal haemolysis, good serum stability and maintained salt resistance. RESULTS: We found that S24 exerted an antimicrobial effect by destroying outer membrane permeability and producing a strong binding effect on bacterial genomic DNA that inhibits genomic DNA migration. Furthermore, S24 exerted a strong ability to promote healing in wound infected by P. aeruginosa, A. baumannii and mixed strains in a mouse model. CONCLUSIONS: Overall, S24 showed good stability under physiological conditions and excellent antimicrobial activity, suggesting it may be a potential candidate for the development of serious bacterial infection treatment.

8.
ACS Nano ; 18(24): 15681-15694, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38848285

RESUMO

The prolonged wound-healing process caused by pathogen infection remains a major public health challenge. The developed electrical antibiotic administration typically requires metal electrodes wired to a continuous power supply, restricting their use beyond clinical environments. To obviate the necessity for antibiotics and an external power source, we have developed a wearable synergistic electroceutical device composed of an air self-charging Zn battery. This battery integrates sustained tissue regeneration and antibacterial modalities while maintaining more than half of the initial capacity after ten cycles of chemical charging. In vitro bacterial/cell coculture with the self-charging battery demonstrates inhibited bacterial activity and enhanced cell function by simulating the endogenous electric field and dynamically engineering the microenvironment with released chemicals. This electroceutical device provides accelerated healing of a bacteria-infected wound by stimulating angiogenesis and modulating inflammation, while effectively inhibiting bacterial growth at the wound site. Considering the simple structure and easy operation for long-term treatment, this self-charging electroceutical device offers great potential for personalized wound care.


Assuntos
Antibacterianos , Dispositivos Eletrônicos Vestíveis , Cicatrização , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Humanos , Camundongos , Staphylococcus aureus/fisiologia , Zinco/química , Escherichia coli , Testes de Sensibilidade Microbiana
9.
Front Plant Sci ; 15: 1373669, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711605

RESUMO

(E)-ß-Farnesene (EBF) serves as the primary component of the alarm pheromone used by most aphid pest species. Pyrethrum (Tanacetum cinerariifolium) exhibits tissue-specific regulation of EBF accumulation and release, effectively mimicking the aphid alarm signal, deterring aphid attacks while attracting aphid predators. However, cultivated chrysanthemum (Chrysanthemum morifolium), a popular and economically significant flower, is highly vulnerable to aphid infestations. In this study, we investigated the high expression of the pyrethrum EBF synthase (TcEbFS) gene promoter in the flower head and stem, particularly in the parenchyma cells. Subsequently, we introduced the TcEbFS gene, under the control of its native promoter, into cultivated chrysanthemum. This genetic modification led to increased EBF accumulation in the flower stem and young flower bud, which are the most susceptible tissues to aphid attacks. Analysis revealed that aphids feeding on transgenic chrysanthemum exhibited prolonged probing times and extended salivation durations during the phloem phase, indicating that EBF in the cortex cells hindered their host-location behavior. Interestingly, the heightened emission of EBF was only observed in transgenic chrysanthemum flowers after mechanical damage. Furthermore, we explored the potential of this transgenic chrysanthemum for aphid resistance by comparing the spatial distribution and storage of terpene volatiles in different organs and tissues of pyrethrum and chrysanthemum. This study provides valuable insights into future trials aiming for a more accurate replication of alarm pheromone release in plants. It highlights the complexities of utilizing EBF for aphid resistance in cultivated chrysanthemum and calls for further investigations to enhance our understanding of this defense mechanism.

10.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612482

RESUMO

Despite serum progesterone being a widely accepted method for luteal phase support during embryo transfer cycles, debates persist regarding the optimal strategy for guiding clinical decisions on progesterone dosages to maximize reproductive outcomes. This retrospective study explored the utility of microRNA (miRNA) biomarkers in guiding personalized progesterone dosage adjustments for frozen embryo transfer (FET) cycles in 22 in vitro fertilization (IVF) patients undergoing hormone replacement therapy. Utilizing MIRA, an miRNA-based endometrial receptivity test, we analyzed patients' miRNA expression profiles before and after progesterone dosage adjustments to determine suitable dosages and assess endometrial status. Despite patients receiving identical progesterone dosages, variations in miRNA profiles were observed in the initial cycle, and all patients presented a displaced window of implantation. Following dosage adjustments based on their miRNA profiles, 91% of patients successfully transitioned their endometrium towards the receptive stages. However, two patients continued to exhibit persistent displaced receptivity despite the adjustments. Given the evident variation in endometrial status and serum progesterone levels among individuals, analyzing miRNA expression profiles may address the challenge of inter-personal variation in serum progesterone levels, to deliver more personalized dosage adjustments and facilitate personalized luteal phase support in IVF.


Assuntos
MicroRNAs , Progesterona , Feminino , Humanos , Fase Luteal , Estudos Retrospectivos , MicroRNAs/genética , Transferência Embrionária , Endométrio
11.
Front Immunol ; 15: 1325998, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601166

RESUMO

Background: The house dust mite (HDM) is widely recognized as the most prevalent allergen in allergic diseases. Allergen-specific immunotherapy (AIT) has been successfully implemented in clinical treatment for HDM. Hypoallergenic B-cell epitope-based vaccine designed by artificial intelligence (AI) represents a significant progression of recombinant hypoallergenic allergen derivatives. Method: The three-dimensional protein structure of Der f 36 was constructed using Alphafold2. AI-based tools were employed to predict B-cell epitopes, which were subsequently verified through IgE-reaction testing. Hypoallergenic Der f 36 was then synthesized, expressed, and purified. The reduced allergenicity was assessed by enzyme-linked immunosorbent assay (ELISA), immunoblotting, and basophil activation test. T-cell response to hypoallergenic Der f 36 and Der f 36 was evaluated based on cytokine expression in the peripheral blood mononuclear cells (PBMCs) of patients. The immunogenicity was evaluated and compared through rabbit immunization with hypoallergenic Der f 36 and Der f 36, respectively. The inhibitory effect of the blocking IgG antibody on the specific IgE-binding activity and basophil activation of Der f 36 allergen was also examined. Results: The final selected non-allergic B-cell epitopes were 25-48, 57-67, 107-112, 142-151, and 176-184. Hypoallergenic Der f 36 showed significant reduction in IgE-binding activity. The competitive inhibition of IgE-binding to Der f 36 was investigated using the hypoallergenic Der f 36, and only 20% inhibition could be achieved, which is greatly reduced when compared with inhibition by Der f 36 (98%). The hypoallergenic Der f 36 exhibited a low basophil-stimulating ratio similar to that of the negative control, and it could induce an increasing level of IFN-γ but not Th2 cytokines IL-5 and IL-13 in PBMCs. The vaccine-specific rabbit blocking IgG antibodies could inhibit the patients' IgE binding and basophil stimulation activity of Derf 36. Conclusion: This study represents the first application of an AI strategy to facilitate the development of a B-cell epitope-based hypoallergenic Der f 36 vaccine, which may become a promising immunotherapy for HDM-allergic patients due to its reduced allergenicity and its high immunogenicity in inducing blocking of IgG.


Assuntos
Hipersensibilidade , Vacinas , Animais , Humanos , Coelhos , Epitopos de Linfócito B , Leucócitos Mononucleares , Inteligência Artificial , Imunoglobulina E , Proteínas de Artrópodes , Hipersensibilidade/terapia , Alérgenos , Pyroglyphidae , Dermatophagoides pteronyssinus , Citocinas/metabolismo , Imunoglobulina G
12.
Front Cell Infect Microbiol ; 14: 1353433, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558854

RESUMO

Objective: To analyze the clinical epidemiological characteristics including clinical features, disease prognosis of pneumococcal meningitis (PM), and drug sensitivity of S. pneumoniae isolates in Chinese children. Methods: A retrospective analysis was performed on the clinical, laboratory microbiological data of 160 hospitalized children less than 15 years of age with PM from January 2019 to December 2020 in 33 tertiary hospitals in China. Results: A total of 160 PM patients were diagnosed, including 103 males and 57 females The onset age was 15 days to 15 years old, and the median age was 1 year and 3 months. There were 137 cases (85.6%) in the 3 months to <5 years age group, especially in the 3 months to <3 years age group (109 cases, 68.2%); S. pneumoniae was isolated from cerebrospinal fluid (CSF) culture in 95(35.6%), and 57(35.6%) in blood culture. The positive rates of S. pneumoniae detection by CSF metagenomic next-generation sequencing (mNGS)and antigen detection method were 40.2% (35/87) and 26.9% (21/78). Fifty-five cases (34.4%) had one or more predisposing factors of bacterial meningitis; and 113 cases (70.6%) had one or more extracranial infection diseases Fever (147, 91.9%) was the most common clinical symptom, followed by vomiting (61, 38.1%) and altered mental status (47,29.4%). Among 160 children with PM, the main intracranial imaging complications were subdural effusion and (or) empyema in 43 cases (26.9%), hydrocephalus in 24 cases (15.0%), cerebral abscess in 23 cases (14.4%), intracranial hemorrhage in 8 cases (5.0%), and other cerebrovascular diseases in 13 cases (8.1%) including encephalomalacia, cerebral infarction, and encephalatrophy. Subdural effusion and (or) empyema and hydrocephalus mainly occurred in children < 1 years old (90.7% (39/43) and 83.3% (20/24), respectively). 17 cases with PM (39.5%) had more than one intracranial imaging abnormality. S. pneumoniae isolates were completely sensitive to vancomycin (100.0%, 75/75), linezolid (100.0%,56/56), ertapenem (6/6); highly sensitive to levofloxacin (81.5%, 22/27), moxifloxacin (14/17), rifampicin (96.2%, 25/26), and chloramphenicol (91.3%, 21/23); moderately sensitive to cefotaxime (56.1%, 23/41), meropenem (51.1%, 23/45) and ceftriaxone (63.5, 33/52); less sensitive to penicillin (19.6%, 27/138) and clindamycin (1/19); completely resistant to erythromycin (100.0%, 31/31). The cure and improvement rate were 22.5% (36/160)and 66.3% (106/160), respectively. 18 cases (11.3%) had an adverse outcome, including 6 cases withdrawing treatment therapy, 5 cases unhealed, 5 cases died, and 2 recurrences. S. pneumoniae was completely susceptible to vancomycin (100.0%, 75/75), linezolid (100.0%, 56/56), and ertapenem (6/6); susceptible to cefotaxime, meropenem, and ceftriaxone in the order of 56.1% (23/41), 51.1% (23/45), and 63.5 (33/52); completely resistant to erythromycin (100.0%, 31/31). Conclusion: Pediatric PM is more common in children aged 3 months to < 3 years old. Intracranial complications mostly occur in children < 1 year of age with fever being the most common clinical manifestations and subdural effusion and (or) empyema and hydrocephalus being the most common complications, respectively. CSF non-culture methods can facilitate improving the detection rate of pathogenic bacteria. More than 10% of PM children had adverse outcomes. S. pneumoniae strains are susceptible to vancomycin, linezolid, ertapenem, levofloxacin, moxifloxacin, rifampicin, and chloramphenicol.


Assuntos
Empiema , Hidrocefalia , Meningites Bacterianas , Meningite Pneumocócica , Derrame Subdural , Adolescente , Criança , Feminino , Humanos , Lactente , Masculino , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cefotaxima , Ceftriaxona/uso terapêutico , Cloranfenicol , Empiema/tratamento farmacológico , Ertapenem/uso terapêutico , Eritromicina/uso terapêutico , Hidrocefalia/tratamento farmacológico , Levofloxacino , Linezolida/uso terapêutico , Meningites Bacterianas/diagnóstico , Meningite Pneumocócica/diagnóstico , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/epidemiologia , Meropeném/uso terapêutico , Testes de Sensibilidade Microbiana , Moxifloxacina/uso terapêutico , Estudos Retrospectivos , Rifampina , Derrame Subdural/tratamento farmacológico , Vancomicina , Recém-Nascido , Pré-Escolar
13.
J Agric Food Chem ; 72(17): 10089-10096, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38626386

RESUMO

Lactoferrin (LTF) has diverse biological activities and is widely used in functional foods and active additives. Nevertheless, evaluating the proteoform heterogeneity, conformational stability, and activity of LTF remains challenging during its production and storage processes. In this study, we describe the implementation of native mass spectrometry (nMS), glycoproteomics, and an antimicrobial activity assay to assess the quality of LTF. We systematically characterize the purity, glycosylation heterogeneity, conformation, and thermal stability of LTF samples from different sources and transient high-temperature treatments by using nMS and glycoproteomics. Meanwhile, the nMS peak intensity and antimicrobial activity of LTF samples after heat treatment decreased significantly, and the two values were positively correlated. The nMS results provide essential molecular insights into the conformational stability and glycosylation heterogeneity of different LTF samples. Our results underscore the great potential of nMS for LTF quality control and activity evaluation in industrial production.


Assuntos
Lactoferrina , Espectrometria de Massas , Lactoferrina/química , Lactoferrina/metabolismo , Glicosilação , Estabilidade Proteica , Animais , Conformação Proteica , Bovinos , Temperatura Alta
14.
ChemSusChem ; : e202400209, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38688856

RESUMO

Polyaniline (PANI) provides an attractive organic platform for CO2 electrochemical reduction due to the ability to adsorb CO2 molecules and in providing means to interact with metal nanostructures. In this work, a novel PANI supported copper catalyst has been developed by coupling the interfacial polymerization of PANI and Cu. The hybrid catalyst demonstrates excellent activity towards production of hydrocarbon products including CH4 and C2H4, compared with the use of bare Cu. A Faradaic efficiency of 71.8 % and a current density of 16.9 mA/cm2 were achieved at -0.86 V vs. RHE, in contrast to only 22.2 % and 1.0 mA/cm2 from the counterpart Cu catalysts. The remarkably enhanced catalytic performance of the hybrid PANI/Cu catalyst can be attributed to the synergistic interaction between the PANI underlayer and copper. The PANI favours the adsorption and binding of CO2 molecules via its nitrogen sites to form *CO intermediates, while the Cu/PANI interfaces confine the diffusion or desorption of the *CO intermediates favouring their further hydrogenation or carbon-carbon coupling to form hydrocarbon products. This work provides insights into the formation of hydrocarbon products on PANI-modified Cu catalysts, which may guide the development of conducting polymer-metal catalysts for CO2 electroreduction.

15.
Plant Physiol Biochem ; 208: 108512, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38493664

RESUMO

Perennial ryegrass (Lolium perenne) is a widely used cool season turfgrass with outstanding turf quality and grazing tolerance. High temperature is the key factor restricting the distribution of perennial ryegrass in temperate and sub-tropic regions. In this study, we found that one HEAT SHCOK TRANSCRIPTION FACOTR (HSF) class A gene from perennial ryegrass, LpHSFA3, was highly induced by heat stress. LpHSFA3 is localized in nucleus and functions as a transcription factor. Ectopic overexpression of LpHSFA3 in Arabidopsis improved thermotolerance and rescued heat sensitive deficiency of athsfa3 mutant. Overexpression of LpHSFA3 in perennial ryegrass enhanced heat tolerance and increased survival rate in summer season as evidenced by decreased EL and MDA, increased number of green leaves and total chlorophyll content. LpHSFA3 binds to the HSE region in LpHSFA2a promoter to constitutively activate the expression of LpHSFA2a and downstream heat stress responsive genes. Ectopic overexpression of LpHSFA2a consequently rescued thermal sensitivity of athsfa3 mutant and enhanced thermotolerance of athsfa2 mutant. Perennial ryegrass protoplasts with overexpression of LpHSFA3 and LpHSFA2a exhibited induction of similar subsets of heat responsive genes. These results indicated that transcription factor LpHSFA3 functions as positive regulator of LpHSFA2a to improve thermotolerance of perennial ryegrass, providing further evidence to understand the regulatory networks of plant heat stress response.


Assuntos
Arabidopsis , Lolium , Termotolerância , Lolium/metabolismo , Termotolerância/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Temperatura Baixa , Arabidopsis/genética
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(2): 131-138, 2024 Feb 15.
Artigo em Chinês | MEDLINE | ID: mdl-38436309

RESUMO

OBJECTIVES: To investigate the clinical characteristics and prognosis of pneumococcal meningitis (PM), and drug sensitivity of Streptococcus pneumoniae (SP) isolates in Chinese children. METHODS: A retrospective analysis was conducted on clinical information, laboratory data, and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country. RESULTS: Among the 160 children with PM, there were 103 males and 57 females. The age ranged from 15 days to 15 years, with 109 cases (68.1%) aged 3 months to under 3 years. SP strains were isolated from 95 cases (59.4%) in cerebrospinal fluid cultures and from 57 cases (35.6%) in blood cultures. The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87) and 27% (21/78), respectively. Fifty-five cases (34.4%) had one or more risk factors for purulent meningitis, 113 cases (70.6%) had one or more extra-cranial infectious foci, and 18 cases (11.3%) had underlying diseases. The most common clinical symptoms were fever (147 cases, 91.9%), followed by lethargy (98 cases, 61.3%) and vomiting (61 cases, 38.1%). Sixty-nine cases (43.1%) experienced intracranial complications during hospitalization, with subdural effusion and/or empyema being the most common complication [43 cases (26.9%)], followed by hydrocephalus in 24 cases (15.0%), brain abscess in 23 cases (14.4%), and cerebral hemorrhage in 8 cases (5.0%). Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old, with rates of 91% (39/43) and 83% (20/24), respectively. SP strains exhibited complete sensitivity to vancomycin (100%, 75/75), linezolid (100%, 56/56), and meropenem (100%, 6/6). High sensitivity rates were also observed for levofloxacin (81%, 22/27), moxifloxacin (82%, 14/17), rifampicin (96%, 25/26), and chloramphenicol (91%, 21/23). However, low sensitivity rates were found for penicillin (16%, 11/68) and clindamycin (6%, 1/17), and SP strains were completely resistant to erythromycin (100%, 31/31). The rates of discharge with cure and improvement were 22.5% (36/160) and 66.2% (106/160), respectively, while 18 cases (11.3%) had adverse outcomes. CONCLUSIONS: Pediatric PM is more common in children aged 3 months to under 3 years. Intracranial complications are more frequently observed in children under 1 year old. Fever is the most common clinical manifestation of PM, and subdural effusion/emphysema and hydrocephalus are the most frequent complications. Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates. Adverse outcomes can be noted in more than 10% of PM cases. SP strains are high sensitivity to vancomycin, linezolid, meropenem, levofloxacin, moxifloxacin, rifampicin, and chloramphenicol.


Assuntos
Empiema , Hidrocefalia , Meningite Pneumocócica , Derrame Subdural , Lactente , Feminino , Masculino , Humanos , Criança , Recém-Nascido , Adolescente , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/epidemiologia , Meropeném , Vancomicina , Levofloxacino , Linezolida , Moxifloxacina , Estudos Retrospectivos , Rifampina , Streptococcus pneumoniae , Cloranfenicol
17.
Analyst ; 149(9): 2594-2599, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38526507

RESUMO

Detection of pathogens is one of the key concerns for hospitals, the food industry, water suppliers, or other environmental engineering practices because pathogens can cause a wide range of infectious risks. Staphylococcus aureus (S. aureus) is one of the most common pathogens that are hazardous to human health and its existence is an important index to the safety of food, environmental sanitation, or medical products. In this study, we prepared an electrode with designed surface multilevel 3D micro/nano protrusions for facile and efficient S. aureus detection. The existence of these multilevel protrusions enhanced the adsorption of S. aureus. Hence, the detection limit could be as low as 10 CFU mL-1. Furthermore, the electrode was also successfully used to detect S. aureus in actual samples, such as milk and artificial human tissue fluid. It was found that the recovery of the reported approach showed no significant difference from that of the traditional plate count method. However, compared with the plate count method, the detection process of our approach is much more time-saving and easy-operating. These advantages of the approach we report, such as high sensitivity, reliability, quickness, and user-friendliness, make it a potential platform for detecting S. aureus in relation to the food industry and clinical diagnosis.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Limite de Detecção , Leite , Staphylococcus aureus , Staphylococcus aureus/isolamento & purificação , Técnicas Biossensoriais/métodos , Leite/microbiologia , Técnicas Eletroquímicas/métodos , Nanoestruturas/química , Humanos , Animais , Eletrodos , Propriedades de Superfície
18.
Compr Rev Food Sci Food Saf ; 23(2): e13311, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38445543

RESUMO

ß-Casein, an important protein found in bovine milk, has significant potential for application in the food, pharmaceutical, and other related industries. This review first introduces the composition, structure, and functional properties of ß-casein. It then reviews the techniques for isolating ß-casein. Chemical and enzymatic isolation methods result in inactivity of ß-casein and other components in the milk, and it is difficult to control the production conditions, limiting the utilization range of products. Physical technology not only achieves high product purity and activity but also effectively preserves the biological activity of the components. The isolated ß-casein needs to be utilized effectively and efficiently for various purity products in order to achieve optimal targeted application. Bovine ß-casein, which has a purity higher than or close to that of breast ß-casein, can be used in infant formulas. This is achieved by modifying its structure through dephosphorylation, resulting in a formula that closely mimics the composition of breast milk. Bovine ß-casein, which is lower in purity than breast ß-casein, can be maximized for the preparation of functional peptides and for use as natural carriers. The remaining byproducts can be utilized as food ingredients, emulsifiers, and carriers for encapsulating and delivering active substances. Thus, realizing the intensive processing and utilization of bovine ß-casein isolation. This review can promote the industrial production process of ß-casein, which is beneficial for the sustainable development of ß-casein as a food and material. It also provides valuable insights for the development of other active substances in milk.


Assuntos
Ingredientes de Alimentos , Leite , Humanos , Feminino , Lactente , Animais , Caseínas , Emulsificantes , Fórmulas Infantis
19.
Food Chem X ; 21: 101215, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38379797

RESUMO

This paper aims to overview the influence of different gels that including hydrocolloids and oleogel on techno-functional changes of dairy foods. The hydrocolloids are widely added to dairy products as stabilizers, emulsifiers, and gelling agents to enhance their texture, or improve sensory properties to meet consumer needs; and the newly developed oleogel, which despite less discussed in dairy foods, this article lists its application in different dairy products. The properties of different hydrocolloids were explained in detail, meanwhile, some common hydrocolloids such as pectin, sodium alginate, carrageenan along with the interaction between gel and proteins on techno-functional properties of dairy products were mainly discussed. What's more, the composition of oleogel and its influence on dairy foods were briefly summarized. The key issues have been revealed that the use of both hydrocolloids and oleogel has great potential to be the future trend to improve the quality of dairy foods effectively.

20.
Food Res Int ; 179: 114006, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342533

RESUMO

To distinguish Chinese milks from different regions, 13 milk samples were gathered from 13 regions of China in this study: Inner Mongolia (IM), Xinjiang (XJ), Hebei (HB), Shanghai (SH), Beijing (BJ), Sichuan (SC), Ningxia (NX), Henan (HN), Tianjin (TJ), Qinghai (QH), Yunnan (YN), Guangxi (GX), and Tibet (XZ). Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with the electronic nose (E-nose) technology, was used to detect and analyze the volatile compounds in these milk samples. The qualitative and quantitative results identified 29 volatile chemicals, and we established a database of flavor profiles for the main milk-producing regions in China. E-nose analysis revealed variations in the odor of milk across different areas. Furthermore, results from partial least squares discriminant analysis (PLS-DA) and odor activity values (OAVs) suggested that seven volatile compounds: decane, 2-heptanone, 2-undecanone, 2-nonanone, 1-hexadecanol, 1-octen-3-ol, and (E)-2-nonenal, could be considered as key flavor compounds in Chinese milk products.


Assuntos
Leite , Odorantes , Animais , Leite/química , China , Cromatografia Gasosa-Espectrometria de Massas/métodos , Odorantes/análise , Análise Discriminante
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